Aggregated Blogs of misterdom

The Accada plateform is now Fosstrak. The name of this prototyping platform implementing a number of the EPC (Electronic Product Code) standards has been changed after a trademark dispute.

Fosstrak is a very valuable tool for the research community working on the Internet of Things since it is the first and only attempt to provide an open-source implementation of the standardized Internet of Things known as the EPC network.

From the main menu choose: System->Preferences->Sessions->Startup Programs. Click Add and select the program you wish to start automatically.

There used to be a time when mobile developers could pick between Java Mobile and ... Java Mobile. Then the Symbian development was opened to the community outside Nokia employees.

Lately the iPhone and its (not tremendously open, to say it in a nice way) SDK came into the picture. I the mean time the Open Set Alliance (pushed by Google and others, but by Google mainly ;-)) joined the trend and announced Android.

For developers this means a lot more choice. Freedom has its limits and whenever I need to decide on which platform to develop what prototype I end up flipping coins.

In http://radar.oreilly.com/2008/07/interest-in-the-iphone-android.html there is an interesting survey with some data about the actual choices of the majority.

To wrap up, Android used to win but since there are now phones on which the iPhone platform runs the trend is getting reversed and the iPhone platform is growing stronger. Guess what the trend is going to be when Android devices will be delivered...

As for Symbian it faces the natural decrease in interest that dominant companies face when real challengers are entering the scene.

What a joy to be a mobile developer lately :-)

1) Get the latest jaxb libraries from: https://jaxb.dev.java.net/

2) Copy the lib folder to the root of your eclipse project

3) Copy this build.xml file which triggers the schema generation to the root of your eclipse project.

4) In build.xml change: srcdir="./ejbModule/eu/socrades/sap/messages"
to make it point to the folder where the classes you want to generate the folder

5) Let's say you want to generate your schema from the class Message.java.
If Message.java uses other classes (which is very likely) you need to add them
to the build.xml class path. To do so right click the build.xml file:
Properties->Run/Debug settings->Edit->Classpath and select the jars to include
(e.g. siiCommonDataStructures) by selection Add JARS...

6) Right click on build.xml and do: Run As->Ant build

7) Your schema should be generated in build/schemas

8) Note that the generated schema is sometimes not perfect and might need some
manual edits (such as adding elements that contain the generated types).

More info on: https://jaxb.dev.java.net/nonav/2.0.2/docs/schemagen.html

We have a Web Service which is supposed to return a complex object (called ServiceInstance) which exposes a method returning a WSDL file (ServiceInstance.getWSDL(). Now, I tried several methods for sending the WSDL file as part of the web service payload. The first one was to create a Document object (DOM document) that would contain the XML structure of the WSDL. However, this approach does not seem to work as the JAXB compiler doesn't know how to serialize a Document.

The second approach was to send it as a String. However, when using this approach the xml tags (namely the "greater than" and "smaller characters") are escaped creating a messy xml that one needs to re-parse on the client side. Well actually there is a work around. On the client side you can do:


DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document xmlDocument = builder.parse
(new InputSource(new StringReader(instances.get(0).getWSDL())));


which will re-create a clean DOM Document from the WSDL represented as a String. Note that this will work for any XML document, not just WSDLs.

I know this is not extremely clean but in our case it was the best solution for two reasons (and I'm really open, no eager, to listen to any better proposal):
1) We can still re-create the XML documents on the client side in an easy manner.
2) We needed the WSDL in the ServiceInstance objects to have a small
memory foot-print (they get out of an in-memory database).